Abstract: A dialysis seating unit has a base that is adapted to receive and support a user; a back support connected with the base, that is adapted to receive and support the user's back; and a pad that is interposed between the user and at least one of the base and the back support. The pad has a grid-pattern array of compartments with alternating compartments being filled with a pad stuffing, to present a checkerboard-like pattern of compartments that have the pad stuffing. In another aspect of the invention, a dialysis seating unit has a back support insert that releasably couples with the back support to effectively narrow the support for a relatively smaller user's back. In yet another aspect of the invention, a dialysis seating unit has a seat insert that releasably couples with the base to effectively narrow the seating area.